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<div class="titlepage"><div><div><h3 class="title">
<a name="boost_asio.reference.DynamicBuffer_v2"></a><a class="link" href="DynamicBuffer_v2.html" title="Dynamic buffer requirements (version 2)">Dynamic buffer
      requirements (version 2)</a>
</h3></div></div></div>
<p>
        A dynamic buffer encapsulates memory storage that may be automatically resized
        as required.
      </p>
<p>
        A dynamic buffer type <code class="computeroutput"><span class="identifier">X</span></code> shall
        satisfy the requirements of <code class="computeroutput"><span class="identifier">CopyConstructible</span></code>
        (C++ Std, [copyconstructible]) types in addition to those listed below.
      </p>
<p>
        In the table below, <code class="computeroutput"><span class="identifier">X</span></code> denotes
        a dynamic buffer class, <code class="computeroutput"><span class="identifier">x</span></code>
        denotes a value of type <code class="computeroutput"><span class="identifier">X</span><span class="special">&amp;</span></code>, <code class="computeroutput"><span class="identifier">x1</span></code>
        denotes values of type <code class="computeroutput"><span class="keyword">const</span> <span class="identifier">X</span><span class="special">&amp;</span></code>,
        <code class="computeroutput"><span class="identifier">pos</span></code> and <code class="computeroutput"><span class="identifier">n</span></code>
        denote values of type <code class="computeroutput"><span class="identifier">size_t</span></code>,
        and <code class="computeroutput"><span class="identifier">u</span></code> denotes an identifier.
      </p>
<div class="table">
<a name="boost_asio.reference.DynamicBuffer_v2.t0"></a><p class="title"><b>Table 13. DynamicBuffer_v2 requirements</b></p>
<div class="table-contents"><table class="table" summary="DynamicBuffer_v2 requirements">
<colgroup>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                <p>
                  expression
                </p>
              </th>
<th>
                <p>
                  type
                </p>
              </th>
<th>
                <p>
                  assertion/note<br> pre/post-conditions
                </p>
              </th>
</tr></thead>
<tbody>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">const_buffers_type</span></code>
                </p>
              </td>
<td>
                <p>
                  type meeting <a class="link" href="ConstBufferSequence.html" title="Constant buffer sequence requirements">ConstBufferSequence</a>
                  requirements.
                </p>
              </td>
<td>
                <p>
                  This type represents the underlying memory as a sequence of @c
                  const_buffer objects.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">mutable_buffers_type</span></code>
                </p>
              </td>
<td>
                <p>
                  type meeting <a class="link" href="MutableBufferSequence.html" title="Mutable buffer sequence requirements">MutableBufferSequence</a>
                  requirements.
                </p>
              </td>
<td>
                <p>
                  This type represents the underlying memory as a sequence of @c
                  mutable_buffer objects.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">x1</span><span class="special">.</span><span class="identifier">size</span><span class="special">()</span></code>
                </p>
              </td>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">size_t</span></code>
                </p>
              </td>
<td>
                <p>
                  Returns the size, in bytes, of the underlying memory.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">x1</span><span class="special">.</span><span class="identifier">max_size</span><span class="special">()</span></code>
                </p>
              </td>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">size_t</span></code>
                </p>
              </td>
<td>
                <p>
                  Returns the permitted maximum size of the underlying memory.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">x1</span><span class="special">.</span><span class="identifier">capacity</span><span class="special">()</span></code>
                </p>
              </td>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">size_t</span></code>
                </p>
              </td>
<td>
                <p>
                  Returns the maximum size to which the underlying memory can grow
                  without requiring reallocation.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">x1</span><span class="special">.</span><span class="identifier">data</span><span class="special">(</span><span class="identifier">pos</span><span class="special">,</span>
                  <span class="identifier">n</span><span class="special">)</span></code>
                </p>
              </td>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">const_buffers_type</span></code>
                </p>
              </td>
<td>
                <p>
                  Returns a constant buffer sequence <code class="computeroutput"><span class="identifier">u</span></code>
                  that represents the underlying memory beginning at offset <code class="computeroutput"><span class="identifier">pos</span></code>, and where <code class="computeroutput"><span class="identifier">buffer_size</span><span class="special">(</span><span class="identifier">u</span><span class="special">)</span>
                  <span class="special">&lt;=</span> <span class="identifier">n</span></code>.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">x</span><span class="special">.</span><span class="identifier">data</span><span class="special">(</span><span class="identifier">pos</span><span class="special">,</span>
                  <span class="identifier">n</span><span class="special">)</span></code>
                </p>
              </td>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">mutable_buffers_type</span></code>
                </p>
              </td>
<td>
                <p>
                  Returns a mutable buffer sequence <code class="computeroutput"><span class="identifier">u</span></code>
                  that represents the underlying memory beginning at offset <code class="computeroutput"><span class="identifier">pos</span></code>, and where <code class="computeroutput"><span class="identifier">buffer_size</span><span class="special">(</span><span class="identifier">u</span><span class="special">)</span>
                  <span class="special">&lt;=</span> <span class="identifier">n</span></code>.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">x</span><span class="special">.</span><span class="identifier">grow</span><span class="special">(</span><span class="identifier">n</span><span class="special">)</span></code>
                </p>
              </td>
<td>
              </td>
<td>
                <p>
                  Requires: <code class="computeroutput"><span class="identifier">size</span><span class="special">()</span> <span class="special">+</span> <span class="identifier">n</span> <span class="special">&lt;=</span>
                  <span class="identifier">max_size</span><span class="special">()</span></code>.<br>
                  <br> Extends the underlying memory to accommodate <code class="computeroutput"><span class="identifier">n</span></code> additional bytes at the end.
                  The dynamic buffer reallocates memory as required. All constant
                  or mutable buffer sequences previously obtained using <code class="computeroutput"><span class="identifier">data</span><span class="special">()</span></code>
                  are invalidated.<br> <br> Throws: <code class="computeroutput"><span class="identifier">length_error</span></code>
                  if <code class="computeroutput"><span class="identifier">size</span><span class="special">()</span>
                  <span class="special">+</span> <span class="identifier">n</span>
                  <span class="special">&gt;</span> <span class="identifier">max_size</span><span class="special">()</span></code>.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">x</span><span class="special">.</span><span class="identifier">shrink</span><span class="special">(</span><span class="identifier">n</span><span class="special">)</span></code>
                </p>
              </td>
<td>
              </td>
<td>
                <p>
                  Removes <code class="computeroutput"><span class="identifier">n</span></code> bytes
                  from the end of the underlying memory. If <code class="computeroutput"><span class="identifier">n</span></code>
                  is greater than the size of the underlying memory, the entire underlying
                  memory is emptied. All constant or mutable buffer sequences previously
                  obtained using <code class="computeroutput"><span class="identifier">data</span><span class="special">()</span></code> are invalidated.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">x</span><span class="special">.</span><span class="identifier">consume</span><span class="special">(</span><span class="identifier">n</span><span class="special">)</span></code>
                </p>
              </td>
<td>
              </td>
<td>
                <p>
                  Removes <code class="computeroutput"><span class="identifier">n</span></code> bytes
                  from the beginning of the underlying memory. If <code class="computeroutput"><span class="identifier">n</span></code>
                  is greater than the size of the underlying memory, the entire underlying
                  memory is emptied. All constant or mutable buffer sequences previously
                  obtained using <code class="computeroutput"><span class="identifier">data</span><span class="special">()</span></code> are invalidated.
                </p>
              </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break">
</div>
<div class="copyright-footer">Copyright © 2003-2024 Christopher M. Kohlhoff<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
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